Avalanche Forecast

Issued: Apr 8th, 2018 4:27PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs and Loose Wet.

mconlan, Avalanche Canada

Kootenay Boundary.

Storm slabs have been reactive to humans and natural activity. Expect the trend to continue, as warming is on its way. Be prudent and assess the snow carefully before travelling into avalanche terrain.

Summary

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

MONDAY: Mostly cloudy, light southwesterly winds, alpine temperature -2 C, freezing level 1700 m rising to 2000 m by late afternoon.TUESDAY: A mix of sun and cloud early-morning then mostly cloudy with rain, accumulation 5 to 10 mm, light to moderate southerly winds, alpine temperature 2 C, freezing level 2500 m dropping to 2000 m over the day.WEDNESDAY: A mix of sun and cloud, light southerly winds, alpine temperature -2 C, freezing level 1700 m.

Avalanche Summary

A widespread natural storm slab cycle was observed on Saturday. The avalanches were small to large (size 1 to 2), 10 to 20 cm thick, and often started in lee terrain features at treeline and alpine elevations. These slabs were also reactive to skiers, either producing small storm slabs or loose dry avalanches.

Snowpack Summary

Around 20 to 40 cm of storm snow fell with strong east switching to southwest winds, redistributing the snow into lee features in exposed terrain. The new snow overlies a melt-freeze crust on southerly aspects and on all aspects at low elevations, and settled snow on shaded aspects at high elevations.The snowpack below this is generally well-settled and strong.

Problems

Storm Slabs

Around 20 to 40 cm of snow fell on the weekend with associated strong southerly winds, with the most in the south of the region. Storm slabs have been reactive to skier traffic and natural activity, particularly in wind-loaded terrain features.

Use ridges or ribs to avoid pockets of wind-loaded snow.Observe for the bond of new snow with the old surface before committing into avalanche terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

Freezing levels are on the rise. Be particularly cautious if you find moist or wet snow, which will be more likely below treeline or on southerly slopes. Watch out in steep and gullied terrain, where small avalanches can have severe consequences.

Avoid sun-exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Use caution above cliffs and terrain traps where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 9th, 2018 2:00PM